Spring plunger switch



Oct. 17, 1950 H. w. BATCHELLER SPRING PLUNGER swITcH Filed Feb. 17, 1948 BY w l1-4k @gif I bodying the ,"invention;4

Patented Oct. 17, 1950 2,526,061 y 'SPRING PLNGER swrron Hughrlt. Batcheller, Newton, Mass., -assignonby mesne assignments, toiArk-Les'Switch Corporatien, ohusetts.

Watertown, Mass, a corporation of Massa- Application February 17, 19.48, Serial No. 8,829

This invention relates to an electricswitch of the spring plunger type including a housing from which projects a plunger, YThe plungerV can` be' pushed inward against the pressure ofia spring to operate the switch, the spring acting to restore the plunger to its projected positionQwhen the pressure on the plunger is removed. rThe plunger carries a bridging conductor which elec# trically connects two Xed contact elements When the plunger is in one position, and is-out ofv contact with the contact elements when the plunger is in its otherfposition. can beiarranged acording to the service desired of the switch. That-iis, they can be located so that the switch is on whenfthe plunger is out and is fo-l* when the plunger is pressed in, or

ture Aof electric switcheaparticularly those of.

relatively small size, the cost of labor is a large item which must be reckoned in the price.v of the switch. Any improvement in the' construction and/orarrangement of parts whichwill make for more rapid assembling reduces byV so ymuch the price which the manufacturer must ask to make and easily assembled and are held together as a unit by a temporary pin. rlhe assembly is thrust into the open end of ashel-l, two ,ears at the open Yend of the shell arey bentov'er to lockthe' assembly therein, andth-epin is thenremoved, leavingv theassembled switchv complete. I

AFor a more complete understanding of the invention, reference may be had to the following description thereof, and to the drawing, of which:

Figure l an isometric View offa switch em- Figure 2 is a plan View of the s'ameon al larger scale;

The Contact elementsj 1 claim. (o1. 20o-159) switch shown in Figure '7, as seen from another angle. u Y

The switch illustrated in the drawing is mounted in a cylindrical casing or shell. l ll, which is open lat one end and has lan. end wall i2 at the other yeilitatethe mounting of the switchon a support-v ing wall.. or panel (not-shown). The open end of the shell l isclosedby a disk le of insulation. VA second disk viii of insulation, havinga central aperture aligned with that in the end wall it, is seated against the end wall l2. Two

Y parallel frame members 25J are secured at one end to the disk ttf each said Vmember khaving a pair `of laterally projecting ears 2l' againstwhich the disk bears. The members Z'project through suitable apertures in the disk I6, the projecting a profit. According to the presenti invention, thev parts whichv go into the shell or casing are quickly portions 2 2 beyond the disk i6 serving' as ter minals for the switch. Each member 2t also has a pair of laterally projecting ears 23 against which the disk IS bears. l Y

Slidably mounted in the stem lll is a plunger 2t of insulationthis plunger carrying at its inner end a bridging conductor 26 which, as shown, is

in the form of a metal disk of greater diameter than the aperture in the disk ES, said conductor, 2t having a peripheral flange 28. The conductor? 25 is secured to the inner end-of the plunger 24 and is adapted to move longitudinally within the shell'when the plunger 2li is pressed. Opposing A the inward motion' of" theplung'er is a helical Y' spring Se, a portion of which is located within a lbore' which extends axially into the plungerfrom .the

inner end thereof.` OneV end of the spring Figure 3 is a section on the line 3-3 of Figure 2 Figure 4 is a fragmentary, elevationalview` of the switch shown in Figure 3, partly broken away ato .show in section; ,u t

Figurev 5 Vis an elevational view of a switch with modied contact elements, a part being broken away to show in section; v Y Figure 6 is a portion of the structure shown in Figure 5, the movable parts being in a different position; i. n

Figure 7 is a partial elevational vview of the assembly switch before the shell is secured; and Figure 8 is a fragmentary elevation of the against the end disk i6. T0 prevent the spring from buckling, a plug 32 is inserted in the end of the spring remote from the plunger,l the plug having an end portion 3ft fitting in a small hole in the center of the disk i6 and :a collar $6 which bears against the disk. The plug is preferably l long enough to extend as far as the disk i8, as

by any suitable fastening means. VAs shown, an extruded lip-d2 from the member 2li is insertedthrough a hole near an end of the strip 40 and 3 is then swaged over to engage against the outer face of the strip so as to hold it in position against the outer face of the frame member. The strip 40 is bent so that it extends through an aperture 43 in the member 20 and its free end portion 44 is disposed radially inward with respect to the member 28 which supports it. The end portions 44 are Contact elements which are adapted to be simultaneously engaged by the ange of the bridging conductor 26 when the plunger is in its normal or outer position, as shown in Figure 3. When the plunger is pressed inward, the bridging conductor 26 moves out of contact with the elements 44 and thus opens the switch until the plunger is released so that the spring 3U can restore it to its normal position.

Figures and 6 show a switch having a structure similar to that hereinbefore described eX- -cepting that the Contact elements are differently formed so as to provide a switch which normally open but which is closed when'the plunger is pressed inward. In this switch, each ycontact element 50 is secured to the outer face rof its frame member 20, as previously described. The strip is bent back sharply so that the strip extends through the aperture d3 and its end portion 52, which is engageable by the bridging conductor 26, is located near the end of the shell remote from the plunger. The bridging conductor is thus normally separated fromv the Contact elements 52 until the plunger is pushed inward to bring the bridging conductor into simultaneous contact with the Contact elements 52 so as to close the switch.

In assembling the parts of the switch, the contact elements 49 or 50 are secured to their respective frame members 20, as hereinbefore described, and two such frame members are secured to a disk I8. The bridging conductor 26 is secured to the plunger 26, this being done conveniently by swinging the end edge of the liner 38 over the adjacent surface of the conductor 26, as indicated in Figure 3. The operator then inserts a spring 30 in the bore of the plunger and a plug 32 in the end of the spring. This plunger assembly is thrust through the central hole in the disk I8 until the conductor 26 bears against the disk. An end disk I6 is then pushed over the end portions 22 of the frame members 2D against the pressure of the .spring 30 until it bears against the ears 23. This `disk is temporarily held in place by thrusting a pin 60 through holes 62 in the members 29, as indicated in Figures 7 and 8.

The pressure of the spring 39 against the 4 disk I6 prevents the pin 60- from prematurely falling out. The parts thus far assembled constitute a unit which can be readily handled without coming apart. This unit is inserted into a shell ID so that lthe plunger projects through the hollow stern I4. A suitable machine is employed to bend a pair of ears 64 at the open end of the shell so that these ears overlap the marginal portions of the disk I6 and, thus, hold the disk against the open end of the shell I0. The assembly pin B0 can be removed then, completing the operation of assembling the switch.

Iclaim:

An electric switch comprising two elongated, rigid, metal frame members, each said member being formed with an aperture and having a pair of laterally projecting ears at an end thereof and a second pair of laterally projecting ears spaced from the other end thereof, an insulation disk secured to said frame members against the ears at the end thereof, a second insulation disk secured to said frame members against the other ears thereof, whereby said other end of each member projects beyond the second disk to serve as a terminal, a contact element mounted on each said frame member, each said element consisting of a strip of resilient metal secured near one end to the outer face of the corresponding frame member and extending through the aperture of said member to present a contact portion inward of the other side of said member, a plunger slidably extending through the first said disk, a bridging conductor carried by said plunger between said frame members and movable into simultaneous Contact with the contact portions of Vsaid Contact elements, and a compressed spring pressing against the second said disk and against said plunger.

HUGHl W. BATCHELLER.

REFERENCES CITED The following references are of record in the fileof this patent:

UNITED STATES PATENTS Number Name Date 985,101 Auth Feb. 21, 1911 1,303,634 Cadieux May 13, 1919 1,408,097 Klein Feb. 28, 1922 1,419,099 Axen June 6, 1922 1,842,524 Hansen Jan. 26, 1932 2,086,136 Reynolds July 6, 1937 2,107,903 Peters Feb. 8, 1938 2,301,874 Hetherington Nov. 10, 1942 2,436,898 Rickmeyer Mar. 2, 1948 

